I notice I have console-kit use flag on and if I correctly understand purpose of console-kit in one user environment in pointless (btw I use mainly fluxbox, a bit of xfce and xmonad). Only me use this laptop, sometime I connect via VNC that all. So, question can I just set -console-kit and reemerge the world without brake the system or should I take some action before??

Rebuilding the system with -console-kit won't break your system, but the kit will be still there. To get rid of it search these forums, there is a thread somewhere about getting rid of kits._________________Please learn how to denote units correctly!

If you need polkit you need consolekit or systemd (installed and running) polkit is needed by e.g. udisks and networkmanager.
Just try emerge -pvc consolekit to see which packages need consolekit.

//edit:
Of course there are other users of consolekit than just polkit, but polkit is the one that is used most often._________________"der mac dennoch wesen geil"
Wolfram von Eschenbach, Parzival (Buch 1, Z. 7).
Ein frühes Statement gegen Windows.